Capacity planning for computer systems involves determining the amount of resources needed to host a proposed amount of work. The proposed amount of work can include a workload, which is a particular unit of work for which utilization of computer resources can be quantified. For example, a workload can be a process or set of processes executing in an operating system (OS) (e.g., a database application). In another example, a workload can be a complete operating environment that includes an OS and applications, such as a virtual machine. Computer resources can include central processing unit (CPU), memory, network, storage, and like type resources included in a computer or multiple computers. Capacity planning software models computer resource utilization for the proposed amount of work. The model attempts to predict if a proposed amount of work can execute given a proposed amount of computer resources without encountering any bottlenecks. A bottleneck can occur if the demand for any computer resource, such as a CPU, exceeds the capacity of the proposed computer resources.